Families torn apart by the deadly September 11 terrorist attacks celebrated Sunday’s killing of Ayman al-Zawahiri, one of the top al-Qaida leaders behind the 2001 attacks, but they continued demanding accountability for the Saudi Arabian government’s alleged role.

Meanwhile, Democratic politicians touted Zawahiri’s death as a major accomplishment for Joe Biden.

The president announced Zawahiri’s killing on Monday during a live televised address from the White House, saying, “Justice has been delivered and this terrorist leader is no more.

“People around the world no longer need to fear the vicious and determined killer.”

Survivors of those killed by the September 11 attacks published a statement on Zawahiri’s killing, expressing gratitude about the al-Qaida leader’s death but expressing a desire to see Saudi Arabia held to account for its alleged role in the terror plot. Fifteen of the 19 hijackers on 9/11 were Saudi nationals.

“This news is also a reminder that in order to achieve full accountability for the murders of thousands on September 11 2001, President Biden must also hold the Saudi paymasters accountable for killing our loved ones,” the national chairperson of 9/11 Families United, Terry Strada, said in a statement.

Referring to a controversial trip Biden took to Saudi Arabia last month where Biden fist bumped the country’s Crown Prince Mohammed bin Salman, Strada added: “The financiers are not being targeted by drones, they are being met with fist pumps and hosted at golf clubs. If we’re going to be serious about accountability, we must hold everyone accountable.”

The organization wrote that they have repeatedly requested meetings with the president about punishing the Saudi Arabia government for September 11, but Biden has refused to meet.

Barack Obama, for whom Biden once served as vice-president, stood prominently among politicians who hailed Zawahiri’s death.

He tweeted in part: “It’s a tribute to President Biden’s leadership, to the members of the intelligence community who have been working for decades for this moment, and to the counter-terrorism professionals who were able to take al-Zawahiri out without a single civilian casualty.”

Obama called Zawahiri’s death “proof that it’s possible to root out terrorism without being at war in Afghanistan”.

The Senate majority leader, Chuck Schumer of New York, in his own statement on Zawahiri on Twitter, added: “This is a major accomplishment to bring to justice one of the world’s most wanted terrorists who helped orchestrate the cold-blooded murder of thousands of my fellow New Yorkers on 9/11.”

Conservatives have had mixed reaction to the announcement of Zawahiri’s killing, with few directly praising Biden for the attack and calling for increased scrutiny of al-Qaida’s presence in Afghanistan.

The Senate minority leader, Mitch McConnell, said in a statement that Biden “deserves credit” for approving the strike that killed Zawahiri, but the Republican stalwart noted that the administration needs a “comprehensive plan” to address al-Qaida in Afghanistan.

The House minority leader, Kevin McCarthy, wrote on Twitter celebrating the “brave Americans who took out the terrorist, [al-Zawahiri]”. McCarthy added that a briefing is needed from the Biden administration to address questions over al-Qaida’s remaining in Afghanistan after the American military’s withdrawal from the region between February 2020 and August 2021.

On Twitter, the Colorado representative Lauren Boebert also praised Zawahiri’s killing, writing that it “is undoubtedly a win for the world”.

“This truly evil man can do no more harm to anyone,” Boebert added. “God bless the USA!”

Zawahiri’s death came after his family had moved into a reported safe house in downtown Kabul, the capital of Afghanistan, according to White House officials.

In the months leading up to his death, the 71-year-old had been spotted several times on a balcony, making al-Qaida propaganda videos.

Zawahiri had just stepped on to the balcony Sunday morning when the drone strike that killed him unfolded.